Thursday, utilized the slot machine (motorized hinge slotting machine by Great Planes) to make hinges in the following control surfaces:
I definitely need more practice with this as I always have a tendancy to tilt the machine towards me causing me to come out the side. That said though, made some solid good ones too, but in most cases takes me a second run to get the slot proper.
Due to the angled portion of the elevators I needed to do the hinges up close to the angled part by hand, using an exacto-knife. For this you go straight in and push along the slot, up and out as you need to get the pieces of balsa out of the hole as you go. I trial fit a hinge along the way to avoid over cutting the hinge slot. I also verified previously cut hinges and made adjustments with the knife where necessary.
In the featured image above you can see where I rounded the leading edge of the stabilizer for a nicer, more aerodynamic, look.
You can see the hinged elevators in the top image below and the hinged ailerons in the bottom image below. You can aslo see where I have done some angle sanding along the hinge edge of the elevators to allow the elevators movement once hinged to the stabilizer. I still need to do this to the ailerons along with rounding the trailing edges.
We were looking at doing the rudder and vertical fin too; however, something wasn’t looking right when we were putting the pieces together for a look so need to figure that out first.
Thursday, I got my hands on the hinging tool again, and this time it worked!
Started by verifying the hinge locations and making clear center marking on both the wing and ailerons… verifying we were using the correct aileron for the side we were working with. Once that was done used a centering tool to mark the center line on the trailing edge around the hinges and along the length of the ailerons.
Yesterday, I cut eight pieces out of 1/4“x1/4” balsa stringers to a length of 11/4“. I then marked the center of them and glued them to the inside leading edge of the ailerons, using wood glue, and clamped them in place. The purpose of this is to provide more support/substance for the hinges. I used weights to ensure the ailerons stayed flat on the surface and clamps to keep the balsa pieces tight while the glue dried. You can see the result in the image above.
Next, I attempted to make the assembly for the bottom back of the wing… I’ll call it the WC assembly. Everything I tried to keep things in place just wouldn’t work, from doing it on the workbench to overtop of a piece of wax paper on the wing itself. I even sanded the angle into the WC edge a bit to see if that would help but due to the awkward way the WC angles below the WDs & WEs when the pieces are flush and needing to be to be to the ‘bottom’, which is what I’m calling the longer side, when upside down I just can’t get everything to come together. I think an attempt at using CA is in order… it is so fast acting you basically get one shot before it sets at getting the piece in place properly.
That is where I’m at. The other thing I can do is sand the front WF assembly so that the WGs are flush with the top of WF as then I can put the balsa sheet (W-SH-7) over top.
Sunday, Peter & I did some more work along the trailing edge of the wing. I started by continuing where we left off cutting down the trailing edge. I took a few more passes with the utility knife and then moved on to using a sanding block to get it flush with the back tip of the ribs. I did my best to ensure I didn’t nick the ribs in the process, but unfortunately I’m not perfect and you can see some light patches where I brushed against them with the sand paper.
Sunday afternoon Peter came over and got caught up on my progress. Since we were done on the fuselage for now we put it aside for safe keeping and focused on the tail control surfaces to start with.
For the rudder, stabilizer and two elevators I prepped them for hinging. At this point I also brought out my new toy (thanks Steph for the Christmas gift 🙂 ), the vise you see in the left image below.
While everything was still pinned to the table I marked two hinge line locations for hinging the rudder to the fin (vertical stabilizer). The elevator hinges were previously marked. Next we clamped the rudder, fin, stabilizer and each elevator into the vise one at a time using some scrap balsa sheeting to protect the pieces from the vise clamps.
On Dec. 18th I could really start to see things coming together as I worked on putting the bondages for all the control surfaces into place.
The first step was to ensure the hinges fit into the slots off the main surfaces (wing for ailerons and fin & stabilizer for the rudder & elevator respectively). Once confident of that and also checked with placement of the corresponding control surface attached as well along with their range of motion it was time to mix up a batch of glue.
Prior to gluing the hinges into the slots I prepped them by spreading Vaseline onto the hinge joints to ensure no glue gets into the join, which would prevent the hinges from working properly, don’t want that! I then applied glue into the slots as best I could as well as onto the hinge and then placed them into the slots.
Once that was done I applied glue to the other end of the hinges, seen above. I kept the container below to try and avoid making a mess from excess glue dripping from the hinge as I applied the glue. Before connecting the control surface I did my best to run glue into the slots on the ailerons, elevator & rudder pushing it in with the stick / using gravity to let it seep into the slots.
I then slid the control surface onto the hinge and confirmed all hinges were in place, movement was there and then left them to sit and dry. This concluded another building session and you can see the result below.
Note: I did one control surface at a time, applying glue to the hinges and connecting using the process above prior to moving on to the next control surface.
Been on a hiatus over Christmas which has allowed me to catch up on my blog posts. I am now all caught up and am hoping to get back to building this week! With luck I won’t get this far behind again, lol. Don’t hesitate to leave a comment and let me know you are out there 🙂